Coreless Fiber by Ixblue Photonics
| Brand | Ixblue |
|---|---|
| Origin | France |
| Manufacturer Type | Authorized Distributor |
| Category | Imported Optical Component |
| Model | Custom Coreless Silica Fiber |
| Component Type | Passive Optical Element |
| Wavelength Range | UV–VIS–NIR (190–2200 nm) |
| Material | High-Purity Fused Silica |
| Cladding Diameter Tolerance | ±0.5 µm |
| Coating Options | Low-Index Polymer, Acrylate, or Polyimide |
| Core Diameter | None (Fully Coreless Structure) |
Overview
Coreless fiber is a specialized passive optical component engineered for precise control of optical power distribution and back-reflection suppression at fiber interfaces. Unlike conventional step-index or photonic crystal fibers, coreless fiber features a homogeneous cross-section composed entirely of high-purity fused silica—without a doped or geometrically distinct core region. This absence of refractive index contrast eliminates guided modes and forces light to propagate in free-space-like conditions within the fiber’s uniform cladding. As a result, it functions as a low-numerical-aperture beam expander, enabling controlled divergence, spatial mode homogenization, and effective reduction of power density at downstream interfaces. Developed and refined by Ixblue Photonics in France, this fiber is optimized for high-fidelity transmission across ultraviolet (190 nm), visible (400–700 nm), and near-infrared (700–2200 nm) spectral bands—making it suitable for ultrafast laser delivery, quantum optics coupling, and high-power fiber laser termination.
Key Features
- Homogeneous fused silica structure with zero core—ensures mode-free propagation and minimal modal dispersion
- Tight dimensional control: cladding diameter tolerance ≤ ±0.5 µm for repeatable splicing and alignment
- Customizable outer diameter options (e.g., 80 µm, 125 µm, 250 µm) to match standard fiber handling systems
- Multiple coating selections—including low-refractive-index polymer coatings for enhanced numerical aperture matching and reduced interfacial Fresnel reflection
- High laser-induced damage threshold (LIDT) > 10 J/cm² at 1064 nm, 10 ns pulse width—validated per ISO 21254
- Low hydroxyl content (< 1 ppm) ensures minimal absorption in UV and mid-IR regions
Sample Compatibility & Compliance
This coreless fiber is fully compatible with standard fusion splicing platforms (e.g., Fujikura FSM-100P, Vytran GPX-3400) and supports arc-based, CO₂-laser, and filament-heated splicing techniques. Its all-silica composition enables hermetic sealing when spliced to single-mode, multimode, or photonic crystal fibers—critical for vacuum-compatible or hermetically sealed optomechanical assemblies. The fiber complies with IEC 60793-2-50 (category A1a for silica-based passive fibers) and meets RoHS Directive 2011/65/EU requirements. Batch-specific test reports include spectral attenuation (≤ 0.2 dB/m @ 1550 nm), geometry verification (core/clad concentricity < 0.3 µm), and mechanical proof testing (≥ 100 kpsi tensile strength).
Software & Data Management
While coreless fiber itself is a passive component, its integration into active optical systems benefits from traceable calibration and documentation workflows. Ixblue provides full material certification packages—including spectral transmission curves, dimensional metrology reports, and LIDT validation data—delivered in standardized PDF and CSV formats. These documents support GLP/GMP-compliant system qualification, particularly in regulated environments such as medical laser device manufacturing (IEC 60601-2-22) or aerospace photonics (MIL-STD-883, method 2010). All documentation adheres to ISO/IEC 17025 traceability standards and may be incorporated into electronic lab notebooks (ELNs) or quality management systems (QMS) supporting FDA 21 CFR Part 11 audit trails.
Applications
- Back-reflection suppression: Inserted between high-power fiber amplifiers and sensitive components (e.g., isolators, modulators) to reduce unwanted feedback below −60 dB
- Photonic crystal fiber (PCF) end-cap termination: Provides mechanical protection and thermal stress relief while maintaining single-mode guidance integrity
- Micron-scale beam shaping: Used in conjunction with lensed fibers or micro-optics for NA-matched coupling into waveguides, biosensors, or integrated photonic chips
- UV/VIS/NIR broadband delivery: Enables stable transmission in spectroscopic setups requiring minimal polarization-dependent loss (PDL < 0.05 dB)
- Quantum optics interfacing: Facilitates low-noise coupling between free-space quantum emitters and fiber networks without introducing parasitic guided modes
FAQ
Can coreless fiber be spliced directly to standard SMF-28?
Yes—using optimized fusion splice parameters (reduced arc power, extended pre-fuse time) to minimize bubble formation and diameter mismatch.
Is low-index coating necessary for all applications?
It is recommended for high-NA coupling scenarios (e.g., to multimode fibers or bulk optics) but optional for low-NA free-space expansion where air-cladding interface suffices.
What is the typical insertion loss when splicing coreless fiber into a SMF chain?
Measured insertion loss ranges from 0.15–0.35 dB per splice, depending on alignment precision and cleave quality—verified via cut-back method per ITU-T G.652.
Are custom lengths and connectorization options available?
Yes—standard lengths are 1 m, 2 m, and 5 m; FC/APC, FC/PC, or bare-fiber termination can be factory-installed under cleanroom conditions (ISO Class 5).
